The Clinical Studies Core is designed to 1) Assist investigators in accessing, selecting, and recruiting cystic fibrosis and control patients for clinical trials, and to husband the patient resources of the Center. 2) Assist investigators in the planning and execution of clinical trials, 3) Provide oversight and/or performance of tests and procedures, including quality control. 4) Provide oversight of collection and processing of biologic specimens, including BAL fluid and cell samples, nasal lavage fluid/cells and nasal epithelial cells from scrapping, sputum (induced and expectorated), exhaled breath condensate, blood, urine, and stool. 5) Maintain a specimen and tissue bank of samples collected from current and former patients 6) Maintain the database for all patients ever seen at the Cleveland CF Center since its inception (1558 total patients;360 active patients) for purposes of patient selection for clinical trials and studies, retrospective clinical studies, and cooperation with various national databases. 7) Facilitate the translation of discoveries made by basic science investigators into clinical investigation where applicable, including the development of outcome measures appropriate for specific studies;and to engage basic scientists to investigate questions identified in clinical practice or clinical studies. This Core makes available our well-characterized patient population for clinical studies, and facilitates the bench to bedside translation of ideas from our basic science labs. The Core-supported clinical projects also generate hypotheses that are in turn returned to basic science labs for more detailed investigation. This is an integral component of the Translational Center.